Question

Даны металлы Медь Магний, массой 40г, обработанные фосфорной кислотой. При реакции выделился газ(9,8). Найдите массовую долю меди.

Answer 1

Если я правильно понял, то дана смесь меди и магния.

3Mg+2H3PO4=Mg3(PO4)2+3H2

Cu+H3PO4=реакция не происходит

ню(H2)=9.8/22.4=0.4375 моль

по УХР ню(Н2)=ню(Mg)=0.4375 моль

m(Mg)=0.4375*24=10.5 грамм

m(Cu)=40-10.5=29.5 грамм

w(Cu)=29.5/40=0.7375(или 73.75%)

Answer 2

Finding the Mass Fraction of Copper in the Reaction

To find the mass fraction of copper in the reaction, we can use the information provided about the reaction and the substances involved.

Given: - Metals: Copper (Cu) and Magnesium (Mg) - Mass: 40g - Reaction with phosphoric acid - Gas produced: 9.8g

Calculation Steps:

1. Determine the Reaction: - The reaction involves copper and magnesium being treated with phosphoric acid, resulting in the production of a gas.

2. Calculate the Mass of Copper: - We need to find the mass of copper in the given sample.

3. Calculate the Mass Fraction of Copper: - Once we have the mass of copper, we can calculate its mass fraction in the given sample.

Solution:

1. Determine the Reaction: - The reaction involves the treatment of copper and magnesium with phosphoric acid, resulting in the production of a gas.

2. Calculate the Mass of Copper: - The mass of the gas produced is 9.8g. - The total mass of the metals (copper and magnesium) is 40g. - Therefore, the mass of the metals (copper and magnesium) = 40g - 9.8g = 30.2g.

3. Calculate the Mass Fraction of Copper: - To find the mass fraction of copper, we need to know the individual masses of copper and magnesium in the sample. - Once we have the individual masses, the mass fraction of copper can be calculated using the formula: Mass Fraction of Copper = (Mass of Copper / Total Mass of Sample) * 100%

4. Mass Fraction of Copper: - The mass fraction of copper can be calculated using the individual mass of copper and the total mass of the sample.

Conclusion:

By following the steps outlined above, we can calculate the mass fraction of copper in the given sample based on the information provided.